Step 1:- Login to your Microsoft Hotmail account.
Step 2:- Click on your user name and go to Account settings.
Step 3:- On Account setting page click on Security and Password.
Step 4:- Now click on Close my account. You can find this option at the bottom of the page.
Step 5:- Verify your account if they ask to verify your account.In verification process they will send you an email with a security code on your alternate email address.
Step 6:-When you will click on Close my Account thereafter a page will appear on you screen.First of all, check your billing information and account balance as shown in screenshot. Click next if your have not any pending amount.If you have any pending amount then you have to clear that amount to delete Microsoft account.